Solenoid valve



Sept. 7, 1965 R. D. RYNDERS ETAL 3,204,923

SOLENOID VALVE Filed July 23, 1962 QH "1N e; MJ@

l UU Y 53 m @2 o G `V u 2 O S bh s 211g Q D u S l INVENTORS. m oberjlnder@ ollas@ United States Patent O 3,204,923 SOLENOID VALVE Robert D.Rynders and William R. Dollase, Racine, Wis., assignors to RacineHydraulics & Machinery, Inc., a corporation of Wisconsin Filed July 23,1962, Ser. No. 211,662 8 Claims. (Cl. 251-129) This invention relates toan improved solenoid valve, and, more particularly, to a solenoid valveand circuit that assists in obtaining proper operation of the valve.

Solenoid valves generally include a solenoid driving the stem of a valvemember to penfor-m the valving function, and are adapted to be remotelyenergized to control the uid flow. A problem often encountered in suchvalves is one in which the valve member does not properly move tocontrol position due to material particles in the [fluid with the resultthat the plunger of the solenoid does not `complete its travel. Whenthis occurs, burn out current in excess of a holding current flowsthrough the solenoid, and if not interrupted in some manner, may Wellburn out the solenoid.

-It is, therefore, an object of this invention to provide a new andimproved solenoid valve.

It is a urther object of this invention to provide an improved solenoidvalve which automatically reactuates when the valve is not completelyclosed.

'It is still a further object of this invention to provide a protectivecircuit for a solenoid valve.

Accordingly, one featureV of the invention is to provide a solenoidcontrol valve including a casing, a valve member movable in the casingto control -uid ow, a solenoid operatively Vconnected to the valvemember for moving the valve member to a control position, circuit meansfor energizing the solenoid, and means responsive to a continuation of aburn out current value caused by the valve member not reaching thecontrol position after a predetermined time for recycling the solenoid.

It is a further feature of this invention to provide a valve protectioncircuit for a valve controlling the flow of fluid comprising: meanshaving an actuating current and a hold-ing current smaller than saidactuating current for actuating the valve; and protective meansconnected in series with said actuating means and responsive to currentflow of the magnitude of the actuating current after a period of timefor removing electrical power from Ithe actuating means for a period oftime and for reapplying the power to said actuating means.

It is a further feature of the invention to provide a signal lightindicating the recycling condition of the solenoid valve.

Further objects and advantages will become apparent from the followingdetailed description taken in connection with the accompanying drawingsin which:

FIG. l is a vertical section through the solenoid controlled valve;

FIG. 2 is a fragmentary bottom plan view of the valve shown in FIG. 1;and

FIG. 3 is a circuit including said valve.

While this invention is susceptible o-f embodiment in many differentforms, there is shown in the drawings and will herein be described indetail an embodiment of the invention with the understanding that thepresent disclosure is to be considered as an exemplication of theprinciples of the invention and is not intended to limit the inventionto the embodiment illustrated. The scope of the invention w-ill bepointed out in the appended claims.

FIGURE 3 generally shows a source of electrical current 1t) connected toa function-responsive switch 11 and to a solenoid 12 and, moreparticularly, the coil of the Patented Sept. 7, 1965 solenoid. Arecycling circuit, indicated generally at 13, completes the electricalcircuit for controlling ope-ration of the solenoid 12. Incorporatedwithin the recycling lcircuit 13 is a heating coil element 14 and aswitch 15, series connected, including a normally closed bi-metal switchcontact 15a. In parallel with the series circuit is a neon light 16. y

The solenoid 112 is shown in FIG. 1 having its core 16a engaging a stem17 of a valve member 18 controlling a rfluid ow to a pair of ports 19and 20.

In operation, the function-responsive switch 1'1 actuates the circuitand applies power to solenoid 12. Current Hows through the bimetallicswitch 115, heating coil element 14, and solenoid 12. The initial ow ofcurrent is heavy, this being the .operating characteristic of asolenoid, and suiiicient ilux is developed by the solenoid to actuatecore 16a and stern 17 to move the valve member 18 to a control position.When the solenoid actuates valve member 18 to its control position, theinductance of the solenoid has increased so that the current is reducedto a holding current which is an amount smaller than that needed orpresent to initially or progressively actuate the solenoid to thatcontrol position.

The heating coil 14 and switch contact 15a are designed so that theholding current ilo-wing through heating coil 14 is not suicient to movethe the bimetallic switch contact 15a suiiiciently to cause i-t to breakthe series circuit.

However, in the event that valve member 18 is prevented from completingits travel, current having a burn out value in excess of the holdingcurrent flows through the solenoid coil and heating element 14. Thiswill heat bimeta-llic contact 15a sufficiently after a time interval tocause it to open `the ser-ies circuit. Thus, the solenoid isde-energized, and it ret-urns to its inactive position. The requirementof a time interval insures that the initial actuation of the solenoidwill not 4open the switch 1-5. After a predetermined time, the.bimetallic contact 15a cools, recloses the switch 15, and reappliespower to the solenoid causing it to attempt to move stem 17. In theevent that the reason for the solenoid plunger not completing its travelis removed, such as material particles in the valve, the valve memberwill be moved to its control position. However, should an obstructionstill be suilicient to prevent arriving at the control position, thesolenoid will continue to recycle on and off until such time as theobstruction is removed. .'I'he light 16, being in parallel with theswitch 15, will be lighted to indicate malfunctioning when the switch 15is open.

The valve generally includes a valve casing 25, first and second endmembers 26 and 27, and the valve member 1-8 having the stem 17 and a rodmember 29 iitted in end member 27. A conical spring 30 is coniinedbetween end member 27 and the valve member 18 for returning the valvemember to the left, as viewed in FIG. 1, from the control position whenpower is removed from solenoid 12.

A plurality of ports and passages v119, 20, 33, 34 and 3'5 are shown inFIG, 2 and two of which are shown in FIGURE l, are provided forcontrolling the ow of a fluid. A plurality of chambers 36, 37, 38, 39and 40 are provided within the valve body and are in iiuid communicationwith individual ones of the passages. The ports 19 and 20 are thecont-rol ports which may be connected to opposite sides of a uid motoror connected in some 'other fashion for control. The passage 35 isconnected to a source of fluid under pressure and communicates with thecentral chamber 38 in the valve casing. The passages 33 and 34communicate with the end chambers 36 and 40 and are suitably connectedto tank. The function of the valve member 18 is to connect the pressurepassage 35 with one `or the other of the ports 19 and 20 and with theother port being connected to tank.

A cover member 50 is provided to close off the end of the valve.

When the valve is inthe position shown in FIG. 1, uid may pass frompassage 35 throughA chamber 38 to chamber 37 and out port 19 to a uidmotor or other device. Fluid may also pass into port 20 through chamber39 and chamber 40, and out through passage 34 to tank or otherconnections. When the solenoid is energized .by the function-responsiveswitch 1X1, stern 17 moves to the right driving the valve member 18 tothe right, compressing conical spring 30. Fluid may now flow frompassage `35 through chamber 38 to chamber 39 and out port 29 and, in asimilar manner, iluid may ow into port 19 to chambers 36 and 37 and `outpassage 33 to tank. However, in the presence of impurities or dirt inthe fluid being controlled, it is possible that the valve member 18might not be able to complete its movement to the control position. Inthat event, the heating coil element 14 actuates the bimetallic switchcontact 15a to open the circuit and the solenoid is de-energized.Conical spring 30 returns valve member 18 to its leftward position. Uponcooling of the bimetallic switch 15, the solenoid is again energized andthe valve member moved to the right. If the impediment to valve travelhas been cleared from the valve, the valve member Will complete itstravel and, if not, the solenoid will be recycled until such time as itis cleared.

It is also possible that an obstruction will hold the valve member 18 inan intermediate position and the solenoid core 16a will be in anintermediate position when the solenoid is de-energized. In thisposition the amount of power applied by the solenoid, uponre-energization, will be greater than if the solenoid were starting withthe ports in initial position. The solenoid 12 operates on alternatingcurrent and achieves higher force values as the solenoid core moves intothe eld of its coil. Subsequent cycles, if the valve member has notreturned, will be attempted at -force values higher than those normallyassociated with actuation of the solenoid when in normal initialposition. Also, when the valve member 18 is stuck, the force of spring30 which normally acts in opposition to the solenoid is removed from thesystem to permit the exertion of even greater effective force by thesolenoid on the blocked valve member to attempt removal of theobstruction.

We claim:

1. A solenoid controlled valve including a casing, a valve membermovable in said casing to control uid ow, a solenoid operativelyconnected to said valve member for moving said valve member to a controlposition, circuit means for energizing said solenoid, and meansincluding said circuit means and elements i-n series in said circuitresponsive to a continuation of a burn out current val-ue caused by thevalve member not reaching a control position after a predetermined timefor recycling the solenoid and valve member.

2. A solenoid operated valve comprising a casing, a valve member in saidcasing, means for moving said Valve member to a rst position, a circuitincluding a solenoid yoperatively associated with said valve member formoving said valve member away from said first position, a normallyclosed switch in series with said solenoid having a movable bimetalliccontact, and a heating coil for said bimetallic element also in serieswith said solenoid responsive onlyto a current flow in excess of theholding current for the solenoid to open said switch and de-energiZesaid solenoid, said bimetallic element upon cooling again closing saidcircuit to again energize said solenoid. 3. A valve as delined in claim2 in which an indicator light is in said circuit in parallel with saidswitch and is lighted upon opening of said switch.

4. A solenoid valve protection circuit for use with a valve controllingyiluid How, comprising: valve actuating solenoid means having anactuating current and a holding current smaller than said actuatingcurrent; and protective means connected in circuit in series with saidsolenoid actuating means and responsive to current ow of the magnitudeof said actuating current after a period of time out not to said holdingcurrent for removing electrical power from said solenoid actuating meansfor a period of time and or reapplying said power to said actuatingmeans.

5. A solenoid controlled valve comprising, a valve casing, a valvemember in said casing having a control position, means for moving saidvalve member away from the control position, a solenoid operativelyassociated with the valve member for moving the valve member to thecontrol position, an operating circuit for said solenoid including aswitch in series with said solenoid, said switch having a movablebi-metal switch contact urged to a normally closed position, a heatingcoil in series with said switch responsive only to a current in excessof a solenoid holding current when the valve member does not reach thecontrol position to actuate said bi-metal contact to an open position toopen said circuit and deenergize said solenoid, cooling of said coil andsaid bimetal contact resulting in closing of said circuit to againenergize the solenoid.

6. An electrical circuit having a solenoid including a core and awinding, said solenoid having characteristics whereby a holding currenthas a certain value with the solenoid core in one position and anactuating current has a greater value with the solenoid core in otherpositions, and detecting means in said circuit in series with saidsolenoid Winding responsive to said actuating ourrent but -not theholding current for detecting location of said core other than at saidone position.

7. A solenoid controlled Valve including a casing, a valve membermovable in said casing to control tluid ilow, a solenoid operativelyconnected to said valve member for moving said valve member to a controlposition, said solenoid having characteristics whereby a holding currenthas a certain value with the solenoid core in one position and `anactuating current has a greater value with the solenoid core in otherpositions, circuit means for energizing said solenoid, and means inseries with said solenoid responsive to a continuation of the actuatingcurrent beyond a predetermined time caused by the valve member notreaching a control position for cutting-ott power to the solenoid.

8. A solenoid valve protection circuit for use with a valve controllingfluid flow, comprising: valve actuating solenoid means having anactuating current and a holding current smaller than said actuatingcurrent; and protective means connected in circuit in series with saidsolenoid actuating means and responsive to current ow of the magnitudeof said actuating current after a period of time but not to said holdingcurrent vfor removing electrical power from said solenoid actuatingmeans.

References Cited bythe Examiner UNITED STATES PATENTS 2,057,384 10/3 6Lamb 317-124 f I:2,436,992 3/48 Ernst 251-129 X 2,914,645 1l/59 Wallace317-132 X M. CARY NELSON, Primary Examiner.

ISADOR WEIL, Examiner,

6. AN ELECTRICAL CIRCUIT HAVING A SOLENOID INCLUDING A CORE AND AWINDING, SAID SOLENOID HAVING CHARACTERISTICS WHEREBY A HOLDING CURRENTHAS A CERTAIN VALUE WITH THE SOLENOID CORE IN ONE POSITION AND ANACTUATING CURRENT HAS A GREATER VALUE WITH THE SOLENOID CORE IN OTHERPOSITIONS, AND DETECTING MEANS IN SAID CIRCUIT IN SERIES WITH SIDSOLENOID WINDING RESPECTIVE TO SAID ACTUATING CURRENT BUT NOT THEHOLDING CURRENT FOR DETECTING LOCATION OF SAID CORE OTHER THAN AT SAIDONE POSITION.